#!/usr/bin/env python
# coding: utf-8

from functools import wraps
from funcsigs import signature

"""
中间件
"""


def typeassert(*ty_args, **ty_kwargs):
    """
    type checker

    :param ty_args:
    :param ty_kwargs:
    :return:
    """
    def decorate(func):
        # If in optimized mode, disable type checking
        if not __debug__:
            return func

        # Map function argument names to supplied types
        sig = signature(func)
        bound_types = sig.bind_partial(*ty_args, **ty_kwargs).arguments

        @wraps(func)
        def wrapper(*args, **kwargs):
            bound_values = sig.bind(*args, **kwargs)
            # Enforce type assertions across supplied arguments
            for name, value in bound_values.arguments.items():
                if name in bound_types:
                    if not isinstance(value, bound_types[name]):
                        raise TypeError('Argument {0} must be {1}.'.format(name, bound_types[name]))
            return func(*args, **kwargs)
        return wrapper
    return decorate

